One of the current trends in consumer electronics is the convergence of television technology and computer technology. Starting with the inclusion of a simple microprocessor chip in a television set, the convergence of the two technologies has evolved into sophisticated personal computers equipped with television tuners and large VGA monitors. Convergence systems enable the user to perform data processing tasks while simultaneously viewing a broadcast television program. The advent of personal satellite receivers has also opened up a vast range of broadcast content.
Data from an external source has long been available to personal computer through dial-up connections to private bulletin boards or public data services such as the Internet. Originally, the computer user had to “pull” the data into the computer by dialing into the service and requesting a download. Later, automatic dial-up utilities were introduced to automate the downloading process when the user was not present. Most recently, “push” technology permits the data service to initiate downloads to a subscriber on a periodic basis assuming the personal computer is on or a scheduling mechanism is available to turn the computer on at the scheduled time.
In the world of broadcast media, such as television, a broadcast channel can transmit data streams as well as audio and video content to a properly equipped tuner/receiver. This transmission method is called “in-band” transmission and currently provides a subscriber with data services such as stock quotes, sports scores, and electronic program guides (EPG) for television schedules. There are multiple ways of transmitting data services in-band. Using EPGs as an example, StarSight Telecast, Inc. places EPG data in the vertical blanking interval in the broadcast television signal while Direct TV™ and Echostar Communications Corp. use a portion of the MPEG2 (Motion Picture Experts Group) data stream broadcast from a digital satellite. The data stream is downloaded to a microprocessor, either in the television or in an attached device, and stored for later processing upon user request.
Because in-band data services frequently modify their data, an updated data stream must be downloaded periodically. However, because the data stream is broadcast in a channel only at certain times, the tuner/receiver must be on and tuned to the correct channel to capture the data at that time. This limitation poses problems for many users who are absent during the times the data stream is being broadcast and do not want to leave their tuner/receiver powered on. Therefore, there is a need for a system that automatically downloads broadcast data from an in-band data service regardless of the presence of the user.